Claude Haiku 4.5 (latest)

Claude Haiku 4.5 is Anthropic's small, speed-oriented entry in the Claude family, positioned as the fast lane for lightweight agents, responsive chat, and routine office tasks where low latency matters more than frontier depth. It belongs to the claude-haiku line and shares Anthropic's broader design philosophy of pairing careful alignment with tool use, while trimming the model for cost-efficient, high-throughput workloads. The closed-weight release makes it available through API providers rather than as a downloadable checkpoint, and it ships with reasoning enabled so it can plan multi-step actions rather than only emit quick replies.

In practice, Claude Haiku 4.5 fits scenarios such as customer support bots, in-IDE assistants, document triage, and back-office automation where a 200,000-token context window gives plenty of room for retrieved passages and conversation history. It reads text and images and writes text, supports tool calling and temperature control, and benefits from prompt caching that drops effective input cost when repeated context is reused. Cataloged pricing across multiple resellers sits near the same low band, making it attractive as a default worker model that can escalate to a larger Claude only on the hardest queries.